You've worked with major construction? I know there are a couple of companies in the region that specialize in internal aquarium builds...the drafting, layout logistics, the whole bit. And of course schedule and cost. You have to contact them first, tell them what you want and go over details (better have a budget first tho).I'm with Sinister-Kisses on this; I'd love to have a giant tank like that, but I'm a firm believer in "If you want it done right...do it yourself!"
We have lots of threads on here detailing DIY tanks that are marvels of careful construction and intelligent design...and we have lots of others that make me wonder how the builder can possibly think that the ideas being used can work. The potential for damage and destruction caused by a dumb mistake at levels like this is almost limitless.
Oh, I see, it's apparently okay if it's inspected by a qualified person? Who exactly is qualified to do this? And why would such a qualified person ever risk his/her reputation on somebody else's DIY job? Once the tank is built, there are some basic aspects of it that can probably be seen and determined to be good enough...or not...but there are many aspects that are simply not visible and not testable. Sure...get an engineer to "inspect" the thing. He charges you $500 and says "all good!" Fill the tank...crack your foundation...flood the house...destroy furnishings, floors...start a nice mould culture growing...and the engineer will, at best, say "Ooops! My bad! Here's your $500 bucks back!"
I've been on too many multi-million-dollar construction projects that were riddled with unbelievable examples of poor design, poor execution and lack of QC to ever trust somebody else, whether they did the work themselves or simply hired some fly-by-night outfit to do it.
SK has it right: "I don't trust anyone".
If I had more space I would LOVE a built in flat hex tank (2ft tall) about 6 feet on the diagonal, or a squared out tank 6'.